What Is The Theory And Principle Behind IVRT?

Posted by TergusPharma on November 25th, 2021

The principle behind IVRT is that human skin is a natural barrier to outside agents. Therefore, the drug products that get administered in semisolid formulations like creams, ointment, and gels must be so that they penetrate the skin to produce an effect. Techniques are employed to determine the dosage form and the route of delivery inside the body. In vitro release testing showcases the promise to release the properties. It reflects the combined effect of both physical and chemical parameters like solubility and particle size of API.

An appropriate methodology analyses skin permeation kinetics like a donor, membrane, and receptor medium. Analysis of all these parameters gets done for drug concentration in IVRT. Drug release from semisolid dosage satisfies a simplified mathematical form of the Higuchi equation (Equation 1)^2. The equation 1 is: Q = 2C0.(DAt/n)/2. Here Q is the amount of drug released per unit area of application, C0 is the initial concentration of a drug, D is the diffusion coefficient of a drug, and t is the time. 

The equation can be applied when the drug gets solubilized in the form of a matrix formulation. Also, the amount of drugs released at the end of the experiment is less than 30%. Drug release amount is proportional to the square root of time. When a graph is present between average cumulative release and time, a straight line gets obtained. The slope of this graph calculates the flux. The mathematical formula for flux calculation is the amount released/ cm2/ h. You have to intend the first 4 to six hours studying the release of a drug. This duration is considered the typical duration of application for a topical product. When novel formulation approaches have altered release profiles, an exception in this behavior may be observed, and equation 1 is invalid. 

IVRT is based on employing techniques in determining an efficient dosage form and route of delivery.